AT A GLANCE

THE VERDICT

If you want foundation-shaking bass and have the floor space to accommodate one (or two) of these beasts, you’ll be the envy of the neighborhood on movie night.

I’ve had a home theater going on 20 years now, and one thing has remained constant through those years: upgrades. It got so bad at one point that my wife had me enter into a contract with her in 2004 that my latest subwoofer upgrade would be my last for the next 10 years. Desperate to make the purchase, I reluctantly agreed and signed my name on the dotted line. Fortunately, the subwoofer just happened to be an SVS PC-Ultra, a cylindrical monster that kept my subwoofer itch scratched for a full decade. But as soon as the contract was up in 2014, I did add a second subwoofer to the mix, a Hsu VTF-15H MK2, which has been filling my room with copious amounts of bass ever since.

As a reviewer, I’m fortunate enough to sample subs in my own home and see how they stack up against my reference gear, though most have been of the compact variety. Then I found out that I had two subwoofers headed my way that are among the biggest—and heaviest—I’d ever auditioned, the SVS PB16-Ultra ($2,499) and SB16-Ultra ($1,999).

On delivery day, the first thing I thought of when the pallet was taken off the truck was that scene in Star Wars where Wedge Antilles first sees the Death Star and declares, “Look at the size of that thing!” Combined, the two subs in their cartons weighed over 350 pounds. Fortunately, my son arrived home from school a couple of hours later and assisted his old man with moving them into the house. First up was the SB16, the sealed-box version and the lighter of the two at 145.9 pounds shipping weight and 122 pounds unpacked. Given its cube-shaped box, getting it onto a handcart and up the three steps into my home wasn’t that difficult. After that warmup, it was time for the PB16, whose rectangular-shaped vented box checks in at a massive 207.3 pounds shipped, or 174.5 pounds naked. Worse still, the crate wouldn’t fit through my front door on the handcart, so we had to manhandle it in ourselves. Luckily, no one was injured and we proceeded to the unboxing of each.

Release the Kraken—or in This Case, Two

The exterior carton of each subwoofer features instructions showing how to properly unpack it. The SB16 came out of its box relatively easily, but the PB16 took three of us to get it out—two pushing, one pulling—in order to free the massive beast. SVS offers two finishes, a piano gloss black or black oak veneer; I was sent the gloss versions. My wife wasn’t thrilled with the size of either sub, but she did comment on how pretty they were and made it a point that I was responsible for keeping them dust free—which turned out to be a daily ritual.

The physics of creating deep bass is a complicated process, but both the SB16 and PB16 are clearly intended to dig deep. Not surprisingly, the siblings share a lot of the same or similar components. First up are their massive proprietary 16-inch drivers, with cones featuring a premium fiberglass resin composite material said to have optimal stiffness-to-mass ratio. They include an 8-inch edge-wound voice coil, which SVS claims is the largest ever deployed in a consumer subwoofer. Generally speaking, larger, highermass drivers are more difficult to control, but by including such a large voice coil in the motor structure, the design is able to utilize the staggering amount of amplification required to do just that. Four toroidal ferrite magnets, combined with an unusually deep basket design, allow the SB16 to reach a 78mm peak-to-peak

Xmech (tech shorthand for “maximum mechanical before damage”) excursion and 65mm peak-to-peak Xmax (shorthand for “maximum linear”) excursion. The PB16, meanwhile, has a 95mm peak-to-peak Xmech excursion and an 82mm peak-to-peak Xmax. Put another way, the SB16 and PB16 cones have a linear range of motion of 2.56 inches and 3.23 inches, respectively. While the woofers are the same size and use similar components, the PB16-Ultra uses an underhung motor (with voice coil windings shorter than the height of the magnetic gap), while the SB16-Ultra uses an overhung motor (voice coil windings longer than the height of the magnetic gap), which is why their excursion specs are slightly different.

In addition to the massive drivers, much of the weight of each sub can be attributed to the MDF construction, which is doubled for the front baffle and reinforced with internal bracing to support the driver and to ensure that it’s housed in an acoustically inert environment. The last thing you want is cabinet resonance ruining your bass party. Each subwoofer is powered by a 1,500-watt continuous-power (and a claimed 5,000-plus-watt peak dynamic power) Sledge Class D amplifier coupled with a 50-megahertz Analog Devices DSP chip. The rear panels of the subwoofers are pretty sparse but include a connector for a detachable power cord, the on/off switch, balanced XLR and single-ended RCA stereo/inputs (and outputs without high-pass filters), and a trigger input.

There’s an App for That

There are controls on each sub’s front panel, but SVS gives you two other great options for making tweaks. Not only do the SB16 and PB16 come with a small IR remote, but you can also download an app from the Play Store or iTunes that will control the subwoofer—or multiple subs—using the Bluetooth wireless link from your phone or tablet. This makes setup a breeze. No more fiddling around with dials on the back—you can make all your adjustments from the money seat with your SPL meter in one hand and your phone in the other.

In addition to setting volume, the app allows you adjust Low Pass Filter, Phase, Polarity, and Room Gain Compensation (to counter bloated bass in some rooms). It even includes a Parametric EQ (PEQ) function, which lets you set the desired center frequency of the filter (from 20 hertz to 200 Hz), increase or decrease the level of its effect, and adjust the bandwidth (Q factor). Additionally, there are three user presets (Movie, Music, and Custom) to save your settings into that can be switched on the fly.

The upper front of each Ultra includes an angled area housing an LED display and four directional controls in case you lose the tiny remote or still own a flip phone that won’t do apps. The well-written manual includes a flow chart of how to navigate through the various settings manually, though these are much easier changed within the app. Each sub includes a detachable rigid perforated metal grille that protects the woofer. Additionally, the grille on the PB16 covers the three 3.5inch flared ports that reside below the driver.

Along with having a vented enclosure, the PB16 has a footprint that’s nearly 50 percent longer than the SB16’s, so it doesn’t easily tuck into a corner. It also has different specs, obviously: The SB16 is rated from 16 to 460 Hz, ±3 decibels, while the PB16 has three different ratings: 15 to 280 Hz ±3 dB in Standard mode (all ports open), 13 to 280 Hz ±3 dB in Extended mode (two ports open), and 14 to 360 Hz ±3 dB in Sealed mode (all ports bunged). As with any sub, placement will also have a huge effect on response.

My home theater is just shy of 5,000 cubic feet, so it definitely needs a big subwoofer or two to pressurize the space. My PC-Ultra sits in the front left-hand corner of the room in a relatively tight space that just fit the SB16-Ultra. The PB16 wouldn’t slip into my usual secondary location and was temporarily placed directly behind our couch in a spot where the bass response makes for one of the best sub locations in the room, but which also put it close to foot traffic. Obviously, if you’re bringing either of these subs into your home permanently, you’ll know exactly where they’re going in advance and have a plan to properly integrate them.

Testing two different subwoofers at once is not an easy chore, but with dual outputs from my pre/pro, I was able to calibrate each sub individually and manually power one off while testing the other. I skipped the Audyssey room correction in my Marantz pre/pro and charted some frequency-response measurements using bass tones and an SPL meter; then I utilized the PEQ function to flatten the response up to 80 Hz. For the PB16-Ultra, this meant doing three different curves: three ports open, one port blocked, and all ports blocked. Thank god for the three presets! Luckily, my room is treated and has a pretty flat response already, so the only required adjustments were around the 40-to-50Hz area, and I was very impressed by the ease of the calibration process using the SVS app.

How Low Can You Go?

I have a demo list of titles to test bass response, and I really wanted to see how deep each of these subs could go. I started by cueing up my old DTS Demo Disc #4 on DVD to play a clip from The Haunting. In this segment, an evil spirit is invading the heroine’s room, and the bass dips well below where you not only hear it but also feel it. Starting with the SB16, I was surprised that my room’s subfloor was vibrating so much. Granted, the spec sheet says it can go down to 16 Hz, but it’s possible that its in-room response goes even lower. I had a similar experience with the ported PB16 when its ports were fully sealed, though with two or all of the ports open, I was even more shocked at how much energy was going into my raised foundation. Subterranean bass, indeed!

Another great low-frequency test is from the Dolby Atmos track on the UHD Pacific Rim Blu-ray, right after we see the Jaeger battle the Kaiju off the coast of Alaska. Battle scarred, but not dead, the Jaeger makes its way to shore where a man and his grandson are searching for hidden treasure with their metal detector. Before you hear the giant coming to shore, you can feel each step it takes. Each subwoofer passed this test with flying colors, regardless of configuration. Just like the T-Rex in Jurassic Park, there were ripples in my water cup as the Jaeger approaches landfall. Yes, my jaw was stuck ajar—man, I love good bass!

Every Christmas season, we have a list of movies that our family enjoys watching, including such classics as A Christmas Story, Elf, and The Grinch Who Stole Christmas. One that made the list this year was The Polar Express. The train arrival scene is another where you can feel the bass before you hear it, and both of these SVS subs are tailormade for this type of effect. You know the train is arriving when the decorations on the boy’s wall start to rattle, and if your subwoofer is up for the challenge, your floor will begin to rumble as well—mine certainly did. As the scene built to a crescendo of smile-inducing bass, the kinetic energy reached deafening reference listening levels. It felt like my house was going to come crumbling down as the windows vibrated and the floor shook mercilessly. Frankly, I’m surprised it didn’t set off the Earthquake Detection System we have in California. Hans Zimmer is one of the best living movie composers, and I streamed a FLAC recording of Track 7 from his Inception soundtrack, “Mombasa.” It proved to me that, despite their large 16-inch woofers, the SVS subs could handle this fast track without muddying the bass response, which features an up-tempo beat that lesser subs noticeably blur.

I tend to run my subs about 2 to 3 dB hot at all times because I like it that way for movies, but I found the PB16-Ultra to be a little bit too overpowering when I ran it at my normal setting with rap music, such as The Beastie Boys, Run D.M.C., and N.W.A, This was easily fixed by lowering the volume a couple of decibels with the IR remote or app until it blended better with my speakers. (This is another good use for the available presets.) The sub level wasn’t as much an issue with the SB16, which blended with my M&K S150 studio monitors with relative ease with the crossover set at 100 Hz, as recommended by SVS’s own Merlin app on their website. Maybe the variation in character and response between the PB16 with ports open and the sealed SB16 had something to do with this difference. It’s hard to say, especially given their positions on opposite ends of my room.

Regardless, the musicality of each sub surprised me. The engineers at SVS certainly spent some time refining these beasts for all sorts of listening scenarios.

So Sad to See You Go

I spent quite a few days listening to the four different scenarios outlined above and came to the conclusion that I really liked the SB16’s sealed sound, especially on music. However, I preferred the PB16 with one port closed (and Extended setting engaged) for bass-intensive scenes from Blu-ray and UHD Blu-ray Discs because of its additional response from 15 to 20 Hz; it really packed a heavy punch when configured this way. Don’t read me wrong: The SB16 and other configurations of the PB16 weren’t weak by any stretch in this area, but this is where the PB16 made the best use of its larger enclosure and extended response setup.

To say I enjoyed my experience with the SB16-Ultra and PB16-Ultra would be an understatement. I love bass, and these two siblings delivered it in spades. If I had to choose one of the two for my particular room, I’d probably go with the SB16—actually, two of them—because its smaller form factor is relevant to my shared theater space and I found it still had plenty of punch on the low end, though the PB16 had a bit more lowdepth impact in my room. Performance aside, I also can’t rave enough about SVS’s app. The setup is easy, and configuring the subs from the comfort of my couch is something I could certainly get used to.

If you truly love bass, you should really give one (or both) of these state-of-the-art subwoofers a try. SVS says they’re made to compete with top-performing subs costing twice or more their price, and after my experience, I don’t doubt they’re a great value. SVS backs up the claim, too, offering a 45-day in-home trial that even includes paying the shipping both ways. They must know that once you hear one of these subs, it’s a one-way trip. Very highly recommended.

Test Bench

SVS PB16-Ultra Subwoofer

This graph shows the quasi-anechoic (employing close-miking of the woofer) frequency response of the PB16-Ultra subwoofer (blue trace).

The PB16-Ultra’s close-miked response in Extended mode, normalized to the level at 80 Hz, indicates that the lower –3dB point is at 15 Hz and the –6dB point is at 13 Hz. The upper –3dB point is at 156 Hz using the LFE input.—MJP

SVS SB16-Ultra Subwoofer

This graph shows the quasi-anechoic (employing close-miking of the woofer) frequency response of the SB16-Ultra subwoofer with controls at default (blue trace), and with the parametric EQ set to +5dB at 20 Hz (green trace).

The SB16-Ultra’s close-miked default response, normalized to the level at 80 Hz, indicates that the lower –3dB point is at 27 Hz and the –6dB point is at 19 Hz. The upper –3dB point is at 174 Hz using the LFE input.

With EQ engaged, normalized to the level at 80 Hz, the lower –3dB point is at 16 Hz and the –6dB point is at 14 Hz.—MJP

Editor’s Note: Using our standard practice of preforming quasi-anechoic measurements at a subwoofer’s default settings, the SB16-Ultra failed to meet the manufacturer’s claimed low-end frequency specification (blue trace). However, it did so handily with an adjustment to the unit’s own integrated EQ (green trace). Users should be able to compensate similarly in their own rooms.—Rob Sabin